It's that time of year again as we get closer to Anime Boston 2018. With that, let's talk about the weather and what to expect. Surprisingly, this is the 4th year I have started this thread so if you want to see the past threads, just click on one of the links:

I think by now, you can get a hint that predicting the weather is unrealistic as it can either be hot or cold and it range from sunny to windy to rain to snow. It is definitely worth preparing for the worst just in case. I'll will check and see later this month to come out with a prediction so stay tuned.

I spent a while looking into the historical weather data available at http://climod2.nrcc.cornell.edu/. There are two long-running, high-quality stations in the area: BOSTON and JAMAICA PLAIN. So I downloaded all the data for those two stations and started playing around with it in a spreadsheet. Then I filtered it to only include March 23-April 8 (a week before and after this year's con dates) and got some stats. Here's what I found:

I spent a while looking into the historical weather data available at http://climod2.nrcc.cornell.edu/. There are two long-running, high-quality stations in the area: BOSTON and JAMAICA PLAIN. So I downloaded all the data for those two stations and started playing around with it in a spreadsheet. Then I filtered it to only include March 23-April 8 (a week before and after this year's con dates) and got some stats. Here's what I found:

The NOAA's Climate Prediction Center has put out their March 30-day and March-April-May 3-month climate forecasts and we can get a bit more information from them.

Note that climate forecasting is a very different thing from weather forecasting. They do not and can not make predictions about individual days this far in advance, but they can say that based on the way La Niña is going plus the current state of the Madden–Julian oscillation, the month as a whole might average out a certain way.

So what do they say for March? Well, here's the temperature map:

march.png (22.4 KiB) Viewed 3521 times

They're saying that for Boston, there's a decent chance that March as a whole averages out to a bit warmer than normal.

Obviously that's nothing we can plan around, but you can treat it as slightly good news.

On the CPC website you can find out more, like the precipitation forecast (normal for us), longer range forecasts (looks like we're in for a hot summer), and the very detailed, capslock-on text forecast.

I've been getting a lot of chatter from local mets about this Spring being on the warmer side as well. However coming from experience, Boston's weather is unpredictable this time of season. Tonight's snowstorm is a great example since most mets were dismissing the storm when it started showing up in models on Monday February 12. Jump to today and they are expecting 2-4 inches of snow in the Boston area by tomorrow morning with snow rate of roughly 1-2 inches per hour. Of course, look at a little later in the week and temps may reach 50F+. Even though they say we may get as high as 70F+ next week, there is no guarantee since I have seen many times where a forecast say 60F+ day 5 days ahead and it ends up being in the upper 40s.

As a general rule of thumb, this is a good idea for us Bostonians:
7+ day forecast - keep the forecast in mind but don't pay much attention to it
5-7 day forecast - watch the forecast but expect major changes
3-5 day forecast - watch the forecast but expect some changes
24+ hour to 3 day forecast - watch the forecast but expect minor changes
Within 24 hour forecast - that is the weather that will mostly happen, unless you are in the transitional seasons (Spring and Fall). In that case, the forecast is accurate about 90% of the time.

As a general rule of thumb, this is a good idea for us Bostonians:
7+ day forecast - keep the forecast in mind but don't pay much attention to it
5-7 day forecast - watch the forecast but expect major changes
3-5 day forecast - watch the forecast but expect some changes
24+ hour to 3 day forecast - watch the forecast but expect minor changes
Within 24 hour forecast - that is the weather that will mostly happen, unless you are in the transitional seasons (Spring and Fall). In that case, the forecast is accurate about 90% of the time.

That's always been the common wisdom going back 100+ years, yea, but I've gotten the impression that forecast modeling has gotten much better over the past few decades. Is that not the case? I've been told by meteorologist types that forecasts today in 2018 are as accurate 3-4 days out as they used to be 12 hours out in the early 90s.

As a general rule of thumb, this is a good idea for us Bostonians:
7+ day forecast - keep the forecast in mind but don't pay much attention to it
5-7 day forecast - watch the forecast but expect major changes
3-5 day forecast - watch the forecast but expect some changes
24+ hour to 3 day forecast - watch the forecast but expect minor changes
Within 24 hour forecast - that is the weather that will mostly happen, unless you are in the transitional seasons (Spring and Fall). In that case, the forecast is accurate about 90% of the time.

That's always been the common wisdom going back 100+ years, yea, but I've gotten the impression that forecast modeling has gotten much better over the past few decades. Is that not the case? I've been told by meteorologist types that forecasts today in 2018 are as accurate 3-4 days out as they used to be 12 hours out in the early 90s.

It is more accurate today than it was in the 90s. However, it is not a 100% accurate when it comes to a 3-4 day forecast, which is why I mention minor to some changes in that area.

With a storm less than 24 hours away and us being in the final stretch before Anime Boston 2018, I thought it would be best to say this... PAY CLOSE ATTENTION TO THE WEATHER.

Now that that got your attention, let me explain. March is coming in like a lion with a powerful storm that will most likely devastate our area. However, that is not the end of it. There are already indications of another strong storms for sometime next week. If the pattern continues, it can go into Anime Boston when it comes around. We are all looking closely at it.

OK, so things have gone from bad to worse... depending on the type of person you are. As of now, the met community is looking at 2 storms very closely, both of which are for snow lovers.

The first storm is suppose to hit our area between March 7 - March 9. As of now, it looks like a good chance of getting 6-12 inches of snow with the Cape getting the least amounts. However, it also looks like a slight shift to the east or west can change those amounts.

The second storm is suppose to hit our area between March 11 - March 14. However, since it is so far away, it is best to concentrate all the focus on the storm for this week and wait until we get closer to the next storm.

I'm slightly north of Boston but we got approximately 14 inches so far...it's still snowing.
Sounds like Boston only got 6 inches or so this storm.

I believe if time passes, everything turns into beauty. If the rains stop, tears clean the scars of memory away. Everything starts wearing fresh colors. Every sound begins playing a heartful melody. Jealousy embellishes a page of the epic. Desire is embraced in a dream. But my mind is still in chaos and..2012 / 2013 / 2014 / 2015 / 2016 / 2017 / 2018

As before, this is not a weather forecast. This is an average over a bunch of different possible scenarios and over a full 2 week date range to come out with a single map. But it does help us narrow down put some probabilities on things.

So here's the maps:

WK34temp-20180309.png (17.22 KiB) Viewed 2950 times

WK34prcp-20180309.png (18.24 KiB) Viewed 2950 times

They're saying there's not enough information to know what's going on temperature-wise, but it's likely that the weeks around AB will be drier than usual.

(Of course, that could mean it's dry before and after con, but raining during, or even a bad dice roll and it's rainy for weeks, but it's better chances for dry.)

Reading into the text discussion we can learn that they use a bunch of different forecast models for making their 3-4 week forecasts, and... they don't agree with each other right now. They're predicting a bunch of different things for major climate patterns like the MJO and the North Atlantic Oscillation, and for the weather systems going through that they affect. Not surprising, since 3-4 weeks out is a long time.

However, they all kind of end up agreeing that the northeast will be drier than usual. And that's not bad news.

A drier AB is all we need. Honestly, if we do not get another major snowstorm after this one and before AB, I can see no snow being on the ground by the time AB comes around.

<Edit> Well, speaking so soon, there is another chance of a storm around March 21. <End of Edit>

Anyway, I think now is a good time to discuss some historical data in regards to past AB Weather.

Since the start of Anime Boston, there have been 4 past AB that falls around the same time of year from this year: AB2010 (April 2-4), AB2015 (April 3-5), AB 2016 (March 25-27), and AB2017 (March 31-April 2).

Temperatures
Of those 4 past Anime Boston, the warmest of the 4 was AB2010 with an average high of 69.33F. The coldest of the 4 was AB2017 with an average low of 33.1F.

Precipitation
Of those 4 past Anime Boston, 3/4 of them had some kind of precipitation with AB2017 being not only the wettest AB of the 4 but also the only one to record snow in the convention's entire history.

Wind
Of the 4 past Anime Boston, the windiest of them all was AB2015 with an average wind of 13.89mph. Of course, the strongest wind gust was recorded in AB2017 at 31.1mph.

Everyone should be prepared as if they had to go outside in the winter in New England. This might be - since we have had a lovely March this year - a very snowy, windy & wet environment. Cosplay & dress accordingly! 5th storm comes Wednesday night & another being talked about week of convention.

"Thou who art darker than even darkness,
Thou who art deeper than even the night!
Thou, the Sea of Chaos, who drifts upon it,
Golden Lord of Darkness!
Hereby I call to thee,
Hereby I swear before thee!
Those who would stand against us,
All those who are fools,
By the power you and I possess,
Grant destruction equally upon them all!
GIGA SLAVE!"

Let's all agree, Anime Boston was extremely lucky this year. By the look of it, there are going to back to back storms in our area with the first of those storms happening this weekend during PAX East. I am going to be looking at the weather data soon but I do not think this AB broke any records.

My experience is weather in New England is unpredictable more than 10 days out. I live 25 miles outside of Boston, the weather here can be different then Boston. Boston has its own weather system due to the tall buildings, tons of concrete and close by the sea shore. The 10 day forecast gets better. The 3 day forecast is mostly right. Always set you weather app to City of Boston. If I have to pick a location I use WBZ or Logan Airport.

The running joke is: If you want to know what the weather is look out the window.

My experience is weather in New England is unpredictable more than 10 days out. I live 25 miles outside of Boston, the weather here can be different then Boston. Boston has its own weather system due to the tall buildings, tons of concrete and close by the sea shore. The 10 day forecast gets better. The 3 day forecast is mostly right. Always set you weather app to City of Boston. If I have to pick a location I use WBZ or Logan Airport.

The running joke is: If you want to know what the weather is look out the window.

Sadly, that is not 100% true. That is because in Weather Apps, Boston is actually Boston Logan Airport. All of the local mets, from professionals to amateurs all agree that having the weather based at Logan is a bad idea. That is because Logan Airport tends to have slightly different weather than somewhere roughly 2 miles away. For example, Logan may have 2 inches of snow while places like Chelsea and Boston Common may have 5 inches of snow; Logan may be 78F with winds of 20mph while Boston's Back Bay area (where Anime Boston takes place) may be 83F with 5mph winds.

Also, another running joke is: If you don't like the weather, wait five minutes.

Edit:
I forgot to mention, I usually tend to post the 14 day, 10 day, 5 day, and 3 day on the forums here just to provide those people not from our area to prepare properly when packing.